How tall are wind turbines?
Modern wind turbines have hub heights that range from approximately 212 feet to 328 feet. Modern turbine blades are longer, stronger and more capable, and range from approximately 110 feet to 135 feet long. Thus, the blade tip at the very top of the wind swept area can be more than 400 feet above ground level, and at the very bottom of the wind swept area is still more than 100 feet above ground level.

Hub heights and blade lengths are selected for each project area based on the character of the wind profile, topography, vegetation and land use, and to comply with zoning and permitting requirements.

How much energy do wind turbines produce?
The rated or maximum capacity of modern land-based wind turbines ranges from 1 MW to 3 MW. A megawatt, MW, is simply one thousand kilowatts, kW. The energy produced by each turbine depends on the wind profile, the turbine power curve and operations, the result of which is expressed as net capacity factor. Each megawatt of wind power serves between 250 to 300 homes on an average day (AWEA, 2007), thus depending on the rated capacity and the net capacity factor, each wind turbine could produce enough energy to supply about 250 to 900 typical homes.

What lighting is used?
The Federal Aviation Association (FAA) dictates lighting requirements for wind turbines, and the requirements have changed over the past ten years and can vary according to the shape of the project area and by the size and location of the project. The prescribed lighting is typically a slow-blinking red light placed on top of the nacelle and generally only visible at night. Many projects utilize synchronous lighting of the perimeter turbines if the shape of the wind farm is conducive to this, and other projects utilize asynchronous lighting of all turbines.

How far away from a house should wind turbines be located?
The advisable minimum distance from an occupied dwelling varies by the size and height of the turbine, the size of the wind farm, and applicable zoning and permitting restrictions. While some landowners want as many turbines on their property as possible, Third Planet Windpower prefers to place turbines no closer than 1,000 feet from an existing occupied dwelling. And in the design of a typical modern wind farm, most turbines are considerably more distant than the minimum requirement.

The zoning for a modern wind farm typically requires minimum setbacks of 1,000 feet from existing occupied dwellings and 400 feet from county roads, but minimum setbacks vary in practice according to the wishes of each local community. Third Planet Windpower believes that appropriate minimum setbacks are important for a variety of technical and aesthetic reasons, and we are happy to collaborate with each local community to recommend minimum setbacks appropriate for their community and project area.

At what wind speeds do wind turbines operate?
The cut-in and cut-out speeds for modern wind turbines vary by model, but the operating wind speed generally ranges from approximately 6 to 55 miles per hour. Modern wind turbines have an elaborate control system, and are designed to shut down in turbulent and high wind speed conditions. As the wind speed increases, the blades on most wind turbines rotate to be more perpendicular to the wind. At the cut-out speed, blades become fully perpendicular to the wind, and are locked in place with a physical brake.

Modern wind turbines are designed to withstand extremely windy conditions, and could be designed to operate at speeds greater than approximately 55 miles per hour, however, this is typically not cost-effective.

What about wind turbines and power lines?
Since wind turbines require access roads for construction and maintenance, collection lines generally run underground along the access roads to the public right-of-way. At some point, the collection lines will combine and run overhead to the breaker station or switchyard for interconnection to the established electric grid.

How does Third Planet Windpower choose locations for wind turbine projects?
Selecting the right place to develop and construct a modern wind farm depends on several factors. The proposed project area must be windy, of course, and windy relative to surrounding areas. Third Planet Windpower prefers compatible underlying land uses, such as ranching, farming or similar uses, with larger parcels. Finding the right point of access to the electric grid is also important, as are the topography, vegetation, road access, utilities, and zoning applicable to the proposed project area.

Perhaps the most important factor is the prevailing attitude of the local landowners and the surrounding community. Wind farming works on a larger scale only if most of the landowners and those in the surrounding community embrace the project. In the right area, a well-developed wind farm results in a strong community acceptance and positive identification with the project.

Landowners with turbines receive attractive royalties and are proud of the additional harvest on their land, other landowners in the immediate project area can be eligible for "buffer zone" payments, and all in the community area benefit from substantial property tax or PILOT payments and the increased economic activity that results from the development, construction and long-term operation of the wind farm.

Are wind turbines noisy?
There are different types of sounds that come from wind turbines. Tonal sound, with distinct frequencies, can result from the individual mechanical components of the turbine or the wind interacting with irregular surfaces (an example of this type of noise is the tone produced by blowing over the top of an open bottle). Broadband sound over a wider range of frequencies results from the interaction of the blades with the wind. There is a specific aerodynamic sound (the "whoosh" or "swish") that occurs as the blade passes in front of the turbine tower, a movement that causes air to be compressed between the blade and the tower.

At a distance of 750 to 1,000 feet from the base of the turbine, measured and modeled data shows that sound pressure levels from the turbine (from all sources) is less than 50 decibels (dBA), similar to a kitchen refrigerator. In rural or low-density areas, there may be little additional sound, but often just the sound of the blowing wind is louder (AWEA, 2007).

Modern wind turbines have been designed with noise reduction features, including sound insulation around the gearbox and generator, less noisy gearboxes, sound insulation throughout the nacelle, and improved rotor blades.

Zoning ordinances for wind projects can vary community by community, but a typical requirement are sound pressure level limits of 50 dBA, or ambient plus 5 dBA, whichever is greater. Third Planet Windpower typically analyzes sound pressure levels in the project area before and after construction of the wind farm to demonstrate compliance with the zoning ordinance, and a well-designed modern wind farm can comply with these standards.

Are wind turbines dangerous to birds and bats?
John Flicker, president of the Audubon Association, wrote an article in the November /December 2006 edition of Audubon Magazine that supports efforts to increase wind energy in the United States. Flicker wrote, "Audubon strongly supports wind power as a clean alternative energy source that reduces the threat of global warming. Location, however, is important" (Flicker, 2006).

Third Planet Windpower typically conducts a comprehensive avian and bat study as a part of its development process, and seeks to avoid sensitive areas. Birds are more than 10,000 times more likely -- at least -- to be killed by other human-related events (e.g., buildings, vehicles, cats, pesticides, etc.) than by a wind turbine (Levesque, 2006).

Do wind turbines interfere with television, radio, satellite, or radar signals?
There are generally two types of these signals, narrow band signals and diffuse signals. Third Planet Windpower typically conducts a communications study as a part of its development process. Narrow band signals are well-mapped and can be easily avoided in most proposed project areas. All obstructions can cause some interference with diffuse signals, but the density of the turbine pedestals in a modern wind farm is unlikely to cause any noticeable interference with diffuse signals such as television, and radio.

The communications study, where relevant, would include a specific review of the potential for interference with Homeland Security installations, which has been an issue for some proposed projects, especially those in the Midwest.

What about turbine shadows?
Because turbines are tall objects on the landscape, they can produce shadows in the early morning and late evening, at least when the sun is shining. The shadow produced by the blades will rotate as the blade turns. The effect is easily predicted based on the location and height of the turbines and the location of the nearby homes (AWEA, 2007).

Third Planet Windpower typically conducts a study of the potential for shadows as a part of its development process. In a well-designed modern wind farm, given setbacks from occupied dwellings and the spacing between turbines, the potential for shadows on any one dwelling is typically just a few hours per year, usually a few minutes per day for a few consecutive days in the Spring and a few consecutive days in the Fall.

Will the wind turbine project damage property values?
Several studies have been performed to evaluate the impact of wind turbine projects on local property values, and two of the most scientific and comprehensive are listed below.

One study performed by ECONorthwest in 2002 interviewed tax assessors in 13 different counties throughout the United States to determine the impact on property values resulting from 22 wind projects built between 1993 and 2000. This study found that property values did not decrease after the installation of the wind turbines, and properties containing wind turbines greatly increased in value (ECONorthwest, 2002).

In 2003, a study performed by the Renewable Energy Policy Project, a Washington, D.C. agency examined all property sales in ten wind farm areas for three years before and after the construction of the wind farms, and found no evidence that the wind farms caused property values to decline. (REPP, 2003)

What local jobs are available with a wind turbine project?
The construction of wind farms requires a substantial amount of local labor, materials and services, including gravel, road material, concrete, and surveying services. Many other products and services can be provided locally, including painting, trucking, staging and storage. A substantial amount of tools and miscellaneous hardware can be provided locally.

The typical wind farm requires up to 200 construction personnel for up to a year for each construction phase, and these workers frequent area motels, restaurants and stores. The number of operating personnel vary according to the size of the wind farm, but the typical wind farm has a business office in the local community with 2 to 6 employees, and an operation and maintenance office in the wind farm area with 5 to 20 employees or more, depending on the number of turbines installed.

Do wind turbine projects pay property taxes?
Property tax regulations vary by state. Since the capital equipment cost of wind farms is significant, wind farms usually make substantial property tax payments, often in rural areas without an existing significant tax base, and provide much needed tax revenue for schools, villages, towns, counties and states. In some states, renewable energy is exempt from property taxes. However, projects in these states can usually enter into an agreement to make regular payments to the local community, often through a "Payment in Lieu of Taxes" (PILOT) program, or otherwise directly negotiated with the local government authority.

How much money will I make by allowing a wind turbine to be constructed on my property?
Third Planet Windpower typically pays landowners the higher of a guaranteed payment or a percentage royalty that can escalate over time with project revenue. Since the typical turbine and access road utilize far less than an acre of land, the yield from wind farming is substantial in comparison to the yield on ranching and farming activities.

What happens when wind turbines wear out?
Wind turbines, like all mechanical equipment, have a limited useful life. The design useful life for a modern wind turbine exceeds 20 years. While these turbines could operate beyond 20 years, with regular maintenance, improvements in technology could justify earlier replacement of turbines or components.

Zoning ordinances will often contain provisions regarding the de-commissioning of the wind farm, and the agreements with each landowner will typically specify the details for the removal of equipment at the end of the project.

Why choose wind energy?
"Wind's exponential growth reflects the nation's increasing demand for clean, safe, and domestic energy, and it continues to attract both private and public sources of capital" (AWEA, 2007). Wind energy was the second leading new power generation installed in the United States in 2006, with more than $4 billion of new capacity installed. The growth of wind energy worldwide exceeded expectations, posting a 41% increase in 2006 that followed a 32% increase in 2005 (Global Wind Energy Council, 2007). In the United States, wind power capacity increased 27% in 2006 (AWEA 2007).

Third Planet Windpower has a passion for the development of clean, cost-competitive energy from the wind. In the right location, energy from a new wind project costs less than energy from a new coal-fired or gas-fired power plant.

Wind energy also produces energy domestically, right in the wind farm community, and wind energy can help decrease our reliance on coal imported from other states or oil imported from other countries.